Callaway Golf's proprietary notching weighting system increases forgiveness and accuracy, even on off-center shots. By removing weight from the center of the club, substantial bulk is removed from the clubhead. This bulk is then relocated to key areas, including the heel and toe and across the back ribbon area. This maximum perimeter weighting helps to square up the clubface, especially on off-center hits. It also increases the MOI for added stability and a more solid feel.